| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [be] [vb pp] on | 7899 |
|
| 2 | [be] concentrate on | 84 |
|
| 3 | [vb pp] concentrate on | 70 |
|
| 4 | [be] [vb pp] concentrate | 7 |
|
